Multimodality Imaging of a Pulmonary Valve Papillary Fibroelastoma Associated With Pulmonary Embolism

Diagnosing cardiac and great-vessel masses is challenging and requires integration of multiple imaging modalities. Papillary fibroelastoma (PFE) of the pulmonary valve is exceptionally rare and can mimic more common entities.

A 79-year-old woman with previous deep venous thrombosis underwent contrast-enhanced thoracoabdominal computed tomography (CT) for constitutional symptoms, which revealed a filling defect that appeared to be in the proximal portion of the main pulmonary artery. Pulmonary embolism was initially suspected, and therapeutic anticoagulation was started. However, transthoracic and contrast echocardiography demonstrated a mobile, contrast-uptaking mass; CT angiography, cardiac magnetic resonance (CMR), and positron emission tomography (PET)/CT further characterized a well-defined, nonvascular but strongly late-enhancing lesion in the pulmonary valve. Lack of response to anticoagulation and imaging features were inconsistent with thrombus or malignancy. Surgical excision was performed, and histopathology confirmed PFE.

This case highlights how systematic multimodality imaging can accurately characterize rare intravascular tumors and prevent misclassification as pulmonary embolism.

Persistent pulmonary artery filling defects that do not regress with anticoagulation should prompt reconsideration of the diagnosis and multimodality imaging to exclude other causes. Integrated use of echocardiography, CT, CMR, and PET/CT enables accurate tissue characterization and guides timely surgical management of PFE.